Hunzeylanines A–E, Five Bisindole Alkaloids Tethered with a Methylene Group from the Roots of Hunteria zeylanica

Abstract

Five novel bisindole alkaloids, hunzeylanines A–E (1–5), with an unprecedented skeleton were isolated from the roots of Hunteria zeylanica. Compounds 1–5 represent the first examples of akuammine–pleioarpamine-type bisindole alkaloids fused with a dihydropyran unit. Their structures including absolute configurations were established through comprehensive spectroscopic data analyses and computational calculation methods. The plausible biogenetic pathway of 1 was also proposed. Alkaloids 1 and 2 displayed moderate cytotoxicity toward three human cancer cell lines (MDA-MB-231, AV3, and Huh7).

Classifying natural products from plants, fungi or bacteria using the COCONUT database and machine learning

“…3). In details, the fungal epicospirocin 1 [33], penicimeroterpenoid A [34], beetleane A [35], funiculolide D [36], and fusoxypenes A [37], the bacterial vertirhodin A [38], bosamycin A [39], and dumulmycin [40], and the plant fortuneicyclidin A [41], meloyunnanine A [42], hyperfol B [43], pegaharmol A [44], hunzeylanine A [45], mucroniferal A [46], perovsfolin A [47], horienoid A [48], and erythrivarine J [49] were correctly classified. On the other hand, the fungal rhizolutin [50] and myxadazoles A [51] and the bacterial marinoterpin A [52] were misclassified.…”

Classifying Natural Products from Plants, Fungi or Bacteria using the COCONUT Database and Machine Learning

“…3). In details, the fungal epicospirocin 1 [33], penicimeroterpenoid A [34], beetleane A [35], funiculolide D [36], and fusoxypenes A [37], the bacterial vertirhodin A [38], bosamycin A [39], and dumulmycin [40], and the plant fortuneicyclidin A [41], meloyunnanine A [42], hyperfol B [43], pegaharmol A [44], hunzeylanine A [45], mucroniferal A [46], perovsfolin A [47], horienoid A [48], and erythrivarine J [49] were correctly classified. On the other hand, the fungal rhizolutin [50] and myxadazoles A [51] and the bacterial marinoterpin A [52] were misclassified.…”

Classifying Natural Products from Plants, Fungi or Bacteria using the COCONUT Database and Machine Learning

“…Among 20 recently reported NPs from plants, fungi, or bacteria, 17 were correctly assigned to their origin, while only two were misassigned (Table 3, Figure 3). In details, the fungal epicospirocin 1, [33] penicimeroterpenoid A, [34] beetleane A, [35] funiculolide D, [36] and fusoxypenes A, [37] the bacterial vertirhodin A, [38] bosamycin A, [39] and dumulmycin, [40] and the plant fortuneicyclidin A, [41] meloyunnanine A, [42] hyperfol B, [43] pegaharmol A, [44] hunzeylanine A, [45] mucroniferal…”